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Topic: C o C (Read 5392 times)

Please can someone tell me what CoC stands for. It keeps cropping up in threads and seems to be a sketch showing how to make something but I'd like to know what the initials stand for. A search on the internet dosen't help at all and a search on here just reveals how many cock-ups we make.

I worked at a small manufacturing place which had to keep CoC stock apart from non-CoC so that they could be compliant for some customers without doing some kind of independant testing or other. Bit vague because well I was a teenager at the time

Yeah 2 years but clearly not a lot of people know this which is odd for a making things forum.How do you know the bit of EN1a you are machining really is what you think it is and not a bit of gummy stick from a backyard in China?Back when it was just a molten pool of metal in a crucible someone took a sample and tested it to make sure it met the necessary EN standard. Only when confirmed by the quick turnround lab was it allowed to be poured into ingots. Then each ingot was carefully stacked seperately from the EN23 etc. As it was rolled/drawn at each stage care was taken to make sure they knew what was what and further tests may have been made to check the composition. When a 10 ton load of bar was to be dispatched to a stockist the site chemist confirmed to the Quality Assurance dept that is was good and a Certificate of Conformity issued with the load. The procedures for all this would be carefully documented and audited for the foundry to achieve ISO9000 acreditation. The company's engineering director and maybe other directors ares legally responsible for teh veracity of this document.The stockist would file the CofC and according to their own auditeed procedures issue a new Cof C when they send out stock. To help tracking they would probably create a Goods Received Note on taking delivery and sometimes inspect it and issue an Inspection Control Note to confirm the analysis.These procedures are pretty much standardised world wide now as ISO9000 is expected for quality products.When the material is made into a product every piece should be traceable right back to the mine it came from and the product can get a CofC itself but that may be Certificate of Compliance to assure that it meets (complies with) the performance specification issued by the buyer. The term Design Certificate may also be used.All this grew out of the Defence Standard 05-21 that made sure military parts were up to standard.

The importance should not be underestimated. It is what ensures you aeroplane was not built with cheapo screws and liable to fall out of the sky at any moment. Any falsification of the documentation can invalidate insurance and land directors and others in jail.

The importance should not be underestimated. It is what ensures you aeroplane was not built with cheapo screws and liable to fall out of the sky at any moment. Any falsification of the documentation can invalidate insurance and land directors and others in jail.

This is OT on C-O-C thread, but really interesting. It is really hard to get 8.8 bolts that are 8.8 class bolts in europe anymore. Least on retail. Sure, the bolt has all markings to indicate that they are 8.8, but quite often they shear when they are tightened with a torque wrench. To my knowledge no stockist, trader or buyer ever have been jailed of taking part of this forgery. How come?

Although it migh explain why car manufactures are defining higher class bolts and using torx, even when it might not be needed. Just making sure that their proper bolt does not get repalced with hardwarestore bolt and when it fails gets bad rap.